Assessment Comments
Assessment is based on: (1) results of chemical/physical monitoring from April to September 2005 at two DNR/UHL TMDL monitoring stations: station 30 NE of New Vienna (STORET station 11310003) and station 28 north of Dyersville (STORET station 11310004), (2) results of USGS monitoring at Dyersville on November 22, 2004, (3) IDNR/UHL biological monitoring in 1999, 2001 & 2005, and (4) the occurrence of two fish kills in 2004, one fish kill in 2006, one fish kill in 2007, and one fish kill in 2008.
Basis for Assessment
[Note: Prior to the 2008 Section 305(b) cycle, this stream segment was designated only for Class B(LR) aquatic life uses. Due to changes in Iowa’s surface water classification that were approved by U.S. EPA in February 2008 (see http://www.iowadnr.com/water/standards/files/06mar_swc.pdf), this segment is now presumptively designated for Class A1 (primary contact recreation) uses. The stream remains designated for aquatic life uses (now termed Class B(WW2) aquatic life uses). Thus, for the current (2010) assessment, the available water quality monitoring data will be compared to the applicable Class A1 and Class B(WW2) water quality criteria.]
SUMMARY: The Class A1 primary contact recreation uses remain not assessed. The Class B(WW2) aquatic life uses remain assessed (monitored) as “not supporting” due to (1) results of IDNR/UHL biological monitoring in 1999, 2001 & 2005 that show regionally poor biological integrity and (2) occurrence of two fish kills in July 2004 a kill in July 2006, a kill in 2007, and an additional kill in 2008. A TMDL for this impairment was approved by U.S. EPA in April 2007 (see http://www.iowadnr.gov/water/watershed/tmdl/files/final/northforkmaq.pdf). Sources of data used for this assessment include (1) results of chemical/physical monitoring from April to September 2005 at two DNR/UHL TMDL monitoring stations: station 30 NE of New Vienna (STORET station 11310003) and station 28 north of Dyersville (STORET station 11310004), (2) results of USGS monitoring at Dyersville on November 22, 2004, (3) IDNR/UHL biological monitoring in 1999, 2001 & 2005, and (4) occurrence of five pollutant-caused fish kills from 2004 through 2008. This segment of the North Fork Maquoketa River and its tributary, Bear Creek, are some of the most fish kill-impacted waters in the state of Iowa.
EXPLANATION: The Class A1 (primary contact recreation) uses remain “not assessed” due to the lack of sufficient data upon which to base an assessment. The Class A1 uses are not assessed due to lack of data upon which to base an assessment. Two samples were collected and analyzed for indicator bacteria in this assessment segment during the previous (2008) assessment/listing cycle. Both samples were collected on July 7, 2005 at IDNR/UHL TMDL monitoring stations NE of New Vienna (STORET station 11310003) (2,300 orgs/100 ml) and north of Dyersville (STORET station 11310004) (2,100 orgs/100ml). This small amount of data neither meets IDNR guidelines for developing Section 305(b) water quality assessments nor allows calculation of summary statistics (i.e., geometric mean) needed to develop such an assessment.
The Class B(WW2) aquatic life used remain assessed as “not supported” due to repeated fish kills and due to results of 1999, 2001 & 2005 biological monitoring showing poor biotic integrity. Despite the reoccurring fish kills in this segment, results of chemical/physical monitoring conducted at the IDNR/UHL TMDL stations, however, suggest relatively good water quality in this assessment segment. None of the combined 26 samples collected at these stations in 2005 exceeded Class B(WW2) criteria for pH or dissolved oxygen. None of the combined 22 samples contained violations of the Class B(WW2) chronic criteria for ammonia nitrogen. Only one sample was collected at the USGS monitoring station at Dyersville; all analytes met Class B(WW2) criteria (i.e., pH, dissolved oxygen, ammonia, DDE, and dieldrin).
Despite chemical/physical water quality that meets applicable aquatic life criteria, the Class B(WW2) aquatic life uses remain assessed (monitored) as “not supported” based, in part, on biological data collected in 1999, 2001 & 2005 as part of the IDNR/UHL stream biocriteria and TMDL development projects. A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the biocriteria sampling data. The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species that were collected in the stream sampling reach. The biological metrics were combined to make a fish community index of biotic integrity (FIBI) and a benthic macroinvertebrate index (BMIBI). The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum). The 1999 FIBI score was 27 (fair). The 2001 FIBI scores were 26, 29 and 33 (all fair) and the BMIBI scores were 46, 46 and 51 (all fair). The 2005 FIBI scores were 37, 36(fair), and the BMIBI scores were 25 (poor) and 47 (fair). The aquatic life use support was assessed as partially supporting (=PS), based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established for previous Section 305(b) reports. The biological impairment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2004. The non-riffle site FIBI BIC for this ecoregion is 44 and the natural substrate BMIBI BIC for this ecoregion is 70. This segment passed the FIBI BIC 0/6 times and passed the BMIBI BIC 0/5 times in the last 10 years. This assessment is considered "monitored" because there were two or more samples collected in multiple years from 2004-2008.
In addition to results of IDNR/UHL biological monitoring that suggest impairment of the Class B(WW2) uses, the ongoing occurrence of fish kills in this assessment segment suggest that the aquatic life uses should be assessed (monitored) as “not supported.” Recent kills occurred in September 2008, January 2007, July 2006, and two fish kills occurred in July 2004. The most recent kill occurred in September 2008; no cause of this kill was identified. Fish carcasses were in relatively good condition and suggested a kill that was 2-5 days old. Positively identified species included blacknose dace, central stoneroller, common shiner, creek chub, johnny darter, southern redbelly dace, and white sucker. No game fish were found in the kill area and the condition on this stream resource is very poor following years of chronic water quality problems and deplorable instream habitat caused by channel straightening, channel maintenance, levy construction, and sediment delivery. Approximately 9431 fish were killed in a 3.1 mile stretch of the North Fork of the Maquoketa River near New Vienna. The value of the fish was estimated to be $4134.08.
The next most recent kill occurred on January 29, 2007 and was attributed to a spill of liquid nitrogen fertilizer. The fertilizer was discharged to a storm drain that emptied into the North Fork of the Maquoketa River. The kill began on the north edge of Dyersville and continued at least 9.5 miles downstream, where there was no access to the stream for the investigation and 100% ice cover prevented the observation of dead fish. However, ammonia levels were over 3.0 ppm at the bridge above Cascade (29.3 miles downstream of the spill location). Approximately 56,542 fish were killed. The estimated value of these fish was $13507.92. At the time of this assessment there are no records that IDNR has sought/received restitution for this fish kill.
The kill in 2006 occurred on or before July 25, 2006 and was attributed overflow from a manure pit and runoff from an open feedlot caused by heavy rain on July 25. Approximately 54,208 fish were killed along a 5.7 mile stretch of the stream. The value of the fish was estimated to be $10738.46. At the time of this assessment there are no records that IDNR has sought/received restitution for this fish kill.
The first kill in 2004 occurred on or before July 6, 2004; no cause of the kill was identified (cause “unknown”). An estimated 200 non-game fish (“minnows” and “suckers”) were killed over approximately 1.5 miles of stream. No estimate of the value of the fish killed was provided. The kill occurred in New Wine Park and upstream in Section 6 of T89N, R2W, Dubuque County. According to the IDNR investigation, the fish had been dead for a few days when they were discovered. The party responsible for the kill was not identified. This segment of the North Fork Maquoketa River has been affected by a number of fish kills over the 1995-2005 period.
A second kill in 2004 that affected this assessment segment occurred on or before July 15, 2004. The kill was caused by a release of manure from an open feedlot dairy operation to an unnamed tributary to the North Fork Maquoketa River. An estimated 200 fish (“minnows”) were killed. Approximately 1 mile of stream was affected. This kill primarily affected the unnamed tributary (location information was not provided for this tributary). The IDNR investigation, however, suggested that the kill could affect the North Fork Maquoketa River [segment IA 01-NMQ-0020-2] as well. According to the IDNR investigation, a plywood stop in a manure control structure failed, releasing an estimated several thousand gallons of manure into the unnamed tributary. The owner of the farm worked quickly to address the spill, constructing an earthen dam, keeping most of the manure contained in the stream and out of the North Fork of the Maquoketa River. The collected manure was applied to cornfields. The manure caused a complete fish kill in the tributary, killing a few hundred creek chubs, stonerollers and minnows. The party responsible for the kill was not identified; IDNR records indicate no attempt to seek restitution for the value of the fish killed.
According to IDNR’s assessment/listing methodology, the occurrence of a single pollutant-caused fish kill, or a fish kill of unknown origin, on a waterbody or waterbody reach during the most recent assessment period (2007-2009) indicates a severe stress to the aquatic community and suggests that the aquatic life uses should be assessed as “impaired.” If a cause of the kill is identified, and the cause is either known, or suspected, to be a “pollutant”, the assessment type is considered “monitored” and the affected waterbody is a candidate for Section 303(d) listing. Fish kills attributed to a pollutant, but where a source of the pollutant was not identified and/or where enforcement actions were not taken against the responsible party, will be placed into Integrated Report subcategory 5b. Since a TMDL was completed for the biological impairment in this stream segment, this assessment was placed in Category 4a for the 2008 assessment/listing cycle and remains in Category 4a for the 2010 cycle.
